My players were defending the village of Celduin and it's fords against the Enemy. One of my players, a big warrior of Beornings was using a two handed axe. He decided to get a shield and one handed axe and when the enemy retreated for a few hours I allowed him to visit the local smithy. There he found a dusty and very, very old shield.
Something like this but much older looking and the tree motif half erased:

I was running wild with ideas in my head when we were playing the game in session, thinking how it got in Celduin from apparantly Gondor. Haven't decided on it's origin and story yet but in terms of game mechanics I have done something like this, during the midnight when the player was fighting against orcs on the bridge for a second, behind the clouds the moon comes up front and shines on the shield. The orcs around the player trembled with fear when the moonlight shone on the tree motif and the one he engaged in combat threw his weapon and ran.
Now this can be a normal event. Orcs knowing the Tree symbol of Gondor may got scared for an instant when it shined with moonlight. Or maybe some higher power were aiding my players and made the moon shine BUT I actually want it to be a "magical item." A very low power one of course.
My player also suspected this and gave the shield to Gloin and asked if he or other dwarves can find any runes on it.
Any ideas?